The present invention is directed generally to an apparatus for moving an article supporting device along a predetermined path and more particularly to a mechanical apparatus for picking up, moving and releasing an article in a predictable and consistent operation.
Article handling machinery have become increasingly popular in recent years, for example in manufacturing operations for picking up and properly positioning a workpiece at the work station of a machine for a particular operation. Existing workpiece handling apparatus have generally had their motion produced either by barrel cams or air cylinders.
Whereas barrel cams driven by a motor and clutch-brake unit produce a predictable and predetermined motion, they incorporate so many cam followers and levers with pivot points that an out-of-tolerance condition can develop in an undesirably short time span. Air cylinder driven units, on the other hand, produce a non-predictable motion. The control of motion is attempted by the use of flow control and cushioning devices which inherently cause a change in motion due to the nature of compressed air and its contaminants.
Accordingly, it is a primary object of the present invention to provide an improved article handling apparatus.
Another object is to provide an article handling apparatus which produces a precise consistent movement.
Another object is to provide an article handling apparatus which is of a relatively simple trouble-free mechanical construction.
A more specific object of the invention is to provide an article handling apparatus which produces a harmonic motion which accelerates and decelerates between zero velocity points coinciding with the pickup and release of an object.
Finally, it is a further object to provide an article handling apparatus which is durable in construction, economical to manufacture and easy to maintain.